Motion-picture-projecting apparatus



March 4, 1930. J. PROKSA 1,749,394

MOTION PICTURE PROJECTING APPARATUS Filed March 21, 1925 3 Sheets-Sheet 1 Q77? 21(7/22'67 4 J07??? Pro/r561,

March 4, 1930. oKs 1,749,394

MOTION PICTURE PROJECTING APPARATUS Filed March 21, 1925 3 Sheets-Sheet 2 J07771 Pro/31 35 Fig. 4 is a section Patented Mar. 4, 1930 101m rnoxsn, or cmcaeo, rumors,

ASSIGNOR 'IO HELIOS CORPORATION, 01'

. CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE MOTIONJIC'I'URE-PROJECTING APPARATUS Application filed March 21, 1925. Serial No. 17,337.

My invention relates to improvements in motion picture projecting apparatus, and particularly to shutter mechanism for mtermittently intercepting the beam of light 5 when the apparatus is in operation. The invention has among its other objects the production of'a mechanism of the kind described, which is extremely neat and attractive in appearance, simple, convenient, compact, durable, reliable, efiicient and satisfactory for use wherever found applicable. A particular object of this invention is the provision of improved mechanism of the kind described, whereby the shutter may be easily synchronized with the film-advancing mech anism when the apparatus is in operation. Many other objects and advantages of the construction herein shown and described will be obvious to those skilled in the art from the disclosures herein given. To this end my invention consists in the novel construction, arrangement and combination of parts herein shown and described, and more particularly pointed out in the claims.

In the drawings, wherein like reference characters indicate like or corresponding parts:

Fig. 1 is a front elevation of apparatus embodying the invention, the shutter being shown in dotted lines;

Fig. 2 is a section taken on line 22 of Fi 1; Fig. 3 is a section taken on line 3-3 of Fig.2;

taken on line H of Fig 2;

Fig. 5 is a detail front elevation of the shutter;

Fig. 6 is Fig 5;

Fig. 7 is Fig. 6; and I Fig. 8 is a detail front elevation of a shutter embod ing another form of the invention. In the rawings, a preferred embodiment a section taken on line 6-6 of a section taken on line 7-7 of of the invention is shown in connection withthe motion picture projecting apparatus, which is more clearly shown and described in my co-pending application, Serial No. 17,336

filed March 21,1925.

secured to a shaft 127, WhlCh This motion picture projecting apparatus includes improved film-feeding mechanism, the major portion of which is enclosed in a housing 30 preferably comprising a bottom plate 31, a top plate 32 and a front wall 33, the front wall being formed integral with the top and bottom plates. Th housing is prefera-bly mounted upon and secured to a motor support 80, which is in turn mounted upon a ble base Rigidly secured which is slidably journaled in the support 80. electrical motor mounted upon the bracket 88 has a shaft 94 to which a friction disk 95 is rigidly secured. The friction disk 95may be brought into and out of driving e'ngagement with friction disks 97 and 98 by means described in the co-pending application in which I have also described and more clearly illustrated means whereby the friction disks 97 and 98 may drive a pinion 128 is rotatably ournaled in the housing 30 (Fig. 3). The plnion 128 meshes with a spur gear sed upon a shaft 151 rotatably journaled n the housing 30, one end of the shaft 151 bemg arranged to project from the housing 30 to receive a crank, or the like, whereby the operator may drive theapparatus if, for any reason, he does not desire to use the motor 90, or if the motor is not available.

Meshing with the meshes with a pinion 161 secured to a shaft 162. Secured to the shaft 162 is a film take-up sprocket drum 164:, which, together application) is adapted to feed the film ast light projecting aperture 346, formed withgear 150 is a gear 156 85 i 166 rigidly secured u 1 integr plo'yed wherever it is found applicable, without departing from the. spirit thereof. Formed integral with the spur gear is a bevel gear meshing with a bevel gear on the lower end of a vertically disposed s aft168, the shaft 168 being rotatably journaled in the housing 30. Also secured to the lower end of the vertically disposed shaft is a spur gpar 172 formed al with a bevel gear 17 which meshes with a bevel gear 178 secured to a shaft 17 9. The shaft 17 9 is rotatably journaled in a bracket' 181 mounted in a hollow how 183 pro ecting from the front wall 33. The 1 racket 181 is rotatably journaled in the hollow boss 183, the bracket 181 being provided with an annular flange 184 seated in a recess 185 turned in the outer end of the hollow boss. A collar 186 secured to the hollow boss 183 go by screws 188 engagps the annular flange 184 and prevents wit drawal of the bracket 181 from the boss. It will be noted that the axis of rotation of the bracket 181'is coincident with the axis of rotation of the shaft as 179. Pinned to the outer end 179 is a pinion 190, which meshes with a inion 191 pinned to a shaft 192 rotatably gprnaled in the bracket 181an'd in a cap 193 ed to the bracket, the axis of the shaft 192 so being eccentrically d' osed with respect to the axis of rotation of e bracket. The shaft 192 may be rotated bodily around the common axis of the shaft 179 and the bracket 181 while the shaft 192 isbeing rotated around 85 its longitudinal axis, the pinion 191 rolling upon the pinion .in a well known manner during such movement of the shaft 192. Carried by the outer end of the shaft 192 is a shutter 194 which preferably comprises two diametrically dis d fan-shaped lades 195 and 196 (Fig. 5), the shutter bein mounted uipona s ider 197 having a sp 198. In 't e re erred embodiment of the invention, the lades 195 .and 196 are both imperforate, but the invention is limited to this construction only in so far as defined in the ap nded claims.

- 198 is rovided with a set screw 200, whereby the sp 't hub 198 may be clamped to the shaft 192 as shown in Fig. 6. The narrow portions of the fan-shaped blades 195 and 196 Q -are disposed adjacent the axis of rotation of the shutter so that the blades increase in width toward the outer ends thereof. en the apparatus is in operation the blades 195 and 196 will alternately intercept the beam of light projected upon the screenin a manner well known to those skilled in the art,

one of the blades being adapted to intercept the beam of light when the film is being advanced and the other blade being adapted to intercept the beam of light during that time a picture is being projected upon the screen.

A handle 205, or its equivalent, may be 9 secured to the bracket 181 to provide means of the shaft A collar 199 seated upon t e hub mechanism so that the beam of light will be intercepted during the entire time the film is in motion. This adjustment may be made during the operation of the apparatus.

The bracket 181 may be secured in th blade which intercepts the beam of light durprojected a picture is being upon a screen negatives the flickering effect produced by the other blade. The rapid changes from dark to light are less pronounced and while the total amount of light projected upon the screen is somewhat less, the strain upon the eyes is lessened.

In Fig. 8 I have shown another form of the invention, wherein a shutter 194i is provided with diametrically disposed fan-shaped blades "195 and 196, the narrow portions of the fan-shaped blades 195 and 196 being disposed ad acent the axis of rotation of the shutter. The shutter 194 is adapted to be used in place of the shutter 194, the blade 195 being adapted to intercept the beam of light when the film is bein advanced, and the blade 196 being adapte to intercept the beam of light during that time a Eicture is being projected upon th the blade 196 is of less width than the blade 195. This construction permits a maximum amount of light to be projected: upon the screen during the opera ion of theapparatus and yet permits the flickering effect of the blade 195 to be balanced out.

Having thus described my invention, it is obvious that various immaterial mo cations may be made in the same without departin from the spirit of my invention;

do not wish to be understood as limiting myself to the exact form, construction, arrangement and combination of parts herein shown and described, or uses mentioned.

What I claim as new an desire to secure by Letters Patent is:

-1. In apparatus in combination, a advancin means, a bracket member mounted upon sai housing to be angularl adjusted around an axis of rotation, a ban e projecting from said bracket member whereby it may be brou ht into angularly adjusted positions man said axis 0 rotation, scre threaded means including a collar able with an annular flange on said'br member for positively clamping it in said angularly adjusted positions, a

housing shaft rotatably journaled .in said bracket member and III having its axis of rotation coincident with a.

said first-mentioned axis of rotation, means for driving said shaft, a second shaft rotatably journaled in said bracket member and having its axis of rotation spaced from the axis of rotation of the first shaft, a gear on said first shaft, a second gear on the second shaft arranged to mesh 'with the first gear, and a shutter mounted upon said second shaft.

2. In an apparatus of the kind described, a housing for encasing film-projecting mechanism, means for displacing the shutter in a plane normal to its axis of rotation comprising a circular recess in said housing, a bracket having an annular flange, said annular flange seated in said recess, a collar secured to said housing and engaging said annular flange to hold same in said recess, a handle on said bracket for adjustably rotating said bracket in said recess, and means for forcing a portion of said collar firmly against said annular flange for holding said bracketin adjusted position.

3. In an apparatus of the kind described,

a housing for encasing film-projecting mechanism, means for displacing the shutter in a plane normal to its axis of rotation comprising a circular recess in said housing, a bracket aving an annular flange, said annular flange seated in said recess, a collar secured to said housing and enga 'ng said annular flange to hold same in sai recess, a handle on said bracket for adjustably rotating said bracket in said recess, and manually operable means for forcing a portion of said collar firmly against said annular flange for holding said bracket in "adj usted position.

- In testimony signed my name.

JOHN PROKSA.

whereof, I have hereunto 

